Rep. Geoff Davis (R-Ky.), who had already announced his retirement, announced late today that he would resign immediately to deal with a "family health issue."

Gov. Steven Beshear (D) can call a special election as early as five weeks after the seat is certified as vacant, but given that the general election is less than 100 days away, insiders expect him to call the special election for Nov. 6, the same day as the general election.

Davis' resignation is thus likely to leave the northern Kentucky seat vacant until November, when Thomas Massie, the GOP nominee for the safe Republican 4th district, will likely to be elected both in the special and general elections. That would allow him to be seated immediately.

"There won't be a primary," former Kentucky Secretary of State Trey Grayson explained to Roll Call. "Both parties will pick their nominees based on party rules."

Insiders see the GOP picking Massie, the tea party-aligned winner of a contentious May primary.

Davis is the 8th House Member to resign this Congress. To see a full list of the Members who left check out our Casualty List.